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Direct answer
Hair and scalp science is a TradeCert Prep study concept connected to Cosmetology State Board Exam Prep prep, not a copied official exam item. Hair and scalp science is one of the core study areas for Cosmetology State Board Exam Prep. Always verify licensing, certification, and testing rules with the current official candidate bulletin, state manual, code book, or testing provider before relying on a detail for compliance.
How to use this answer
Read the answer once, then prove it by choosing an answer in a practice question before looking at the explanation. If the miss repeats, tag the domain as Study module and drill a smaller set before returning to mixed practice.